A guard can perform several functions including: • denying bodily access • containing ejected parts, tools, off-cuts or swath • preventing emissions escaping • forming part of a safe working platform. Guarding is commonly used with machinery and equipment to prevent access to: • rotating end drums of belt conveyors • moving augers of auger conveyors • rotating shafts • moving parts that do not require regular adjustment • machine transmissions, such as pulley and belt drives, chain drives, exposed drive gears • any dangerous moving parts, machinery and equipment.
Interlock guarding occurs when the act of moving the guard (opening, sliding or removing) to allow access, stops the action of the hazardous mechanism. Interlock guarding works by: • disconnecting the drive mechanism mechanically (e.g. applying a brake or disengaging a clutch or geared mechanism) • isolating the power source of the drive mechanism (e.g. stopping the motor) • a combination of mechanical and power disconnection.
When thinking about safe access to machinery and equipment, consider the following: • who will be working on or around the machinery and equipment • people who are required to work in enclosed areas where the atmosphere could be harmful, such as pits, tanks or storage vessels • what equipment or materials need to be carried to undertake the task • where and when is access required for operation, maintenance and cleaning • how will people gain safe access (walkway, gantry, elevated work platform or ladder) • what work will be carried out during access • will people be near or exposed to an unidentified mechanical or non-mechanical hazard at the time of access • has consultation occurred with workers or contractors regarding how they intend to gain access, and what equipment and work platform or structure is best suited for the intended task.
Emergency retrieval plans should allow for immediate local response in safely retrieving people to avoid fatalities.